Who amongst us hasn’t pulled an ‘all-nighter’ to complete an assignment or study for an examination? Now a new study conducted at the University of California, Los Angeles (UCLA) and published in the journal Child Development, has disparaged the practice. Researchers tracked 535 Los Angeles students for two weeks, monitoring their cognition in class, how long they slept at night and their academic scores on tests or homework. The study found that those students who were sleep deprived functioned poorly in class.

A second study, from the University of York in the UK, says that the reason that sleep is so important for children is that it allows their brains to consolidate knowledge acquisition in their long-term memories.

Yet, despite these two new studies – which were, in turn, based on years of similar research – schools tend to load students with homework and extracurricular activities. A lack of sleep is profoundly dangerous, says Matt Carver from the University of Washington, because it’s a complex process that fulfils a number of needs. At night, once the neurons in the brain have synchronised into a regular rhythm, says Carver, the body begins to repair itself. The immune system is restored, muscles and cardiovascular systems are rejuvenated and the positive effects on metabolism and muscle growth from exercise take effect.

But it’s towards the end of a typical six- to eight-hour night of sleep that the most crucial activity happens in the brain. “In Rapid Eye Movement (REM) sleep, your brain is basically replaying everything that happened during the day and consolidating what you’ve learned,” explains Carter. And, during REM sleep, the brain purges the unnecessary details to make room for new learning the following day. If a student doesn’t sleep enough, he won’t spend much time in REM.

The solution to the problem, says Carver and others like author Madeline Levine (Teach Your Children Well, Harper Collins, 2012), is to start the school day at 10:00 and to help students and parents understand the importance of establishing a routine to ensure nightly quality sleep.